Cortez Bank Marine ForecastSan Diego Offshore
Updated Fri Sep 4, 2026
No-go weekend: confused seas and building swell all three days
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Marine Forecast for Cortez Bank Sep 4–6, 2026
📋 No-go weekend: confused seas and building swell all three days
NO-GO Friday: light 9-17 knots NW winds but a confused cross-sea with SW swell crossing NW wind-waves makes for uncomfortable, unpredictable motion. Waves build from 5 to over 6.5 feet through the day and turn bad after 8:00 PM. Not safe for recreational boating despite the tame wind numbers.
NO-GO Saturday despite light 6-14 knots NW winds - a SSE swell crossing NW wind-waves creates confused seas early on, and wave heights stay elevated near 7-7.3 feet all day. Waves are rated bad for all 24 hours, so this is not a safe day to launch.
NO-GO Sunday: winds are light at 8-13 knots N/NNW, but a building S swell at 11-12 second periods pushes waves to 7.3-7.7 feet, rated bad for all 24 hours. Sea state alone makes this an unsafe day for boating despite calm winds.
This entire period is a NO-GO due to persistent cross-seas where southerly to southwesterly swell trains collide with northwest wind-waves, producing confused, uncomfortable sea states even though winds stay light to moderate. Wave heights climb from around 6-7 feet on Friday to over 8 feet by Sunday, and the mismatched wave trains make for awkward, unpredictable boat motion regardless of the manageable wind speeds.
Recent days at Cortez Bank
Today’s Water at Cortez Bank
Sea surface temperature and chlorophyll around Cortez Bank, imaged fresh every morning. Water at the star is 70.8°F today, and chlorophyll of 0.15 mg/m³ reads as blue-green transition water at the spot.
Imagery: Sep 4, 2026 · rebuilt every morning
These charts show you the breaks. DeepCast reads them. A zone-by-zone AI fishing report for these exact waters — temperature edges, color changes, and structure, analyzed together — for $4.99.
Get the AI fishing reportSST and chlorophyll from the SeaLegs AI DeepCast satellite pipeline. Charts are a planning aid — always check the official marine forecast before making the run.
About Cortez Bank
Cortez Bank is the serious end of San Diego offshore water — a remote, shallow seamount about 100 miles off San Diego, known for world-class fishing and the giant open-ocean swell that breaks at Bishop Rock. It is fully exposed: no island lee, no shelter, and swell that arrives with its full Pacific fetch intact. A careful read of swell height and period is essential before committing to the crossing.
The outlook below updates every morning from the latest marine model data, with a plain GO / CAUTION / NO-GO call for each day — the same AI rating used in the SeaLegs AI app.
Reading conditions at Cortez Bank
Long-period Pacific swell is the defining variable out here. The same 5-foot reading can be a well-organized 13-second swell that a sportfisher rides comfortably — or a shorter, wind-driven sea that makes the whole crossing a grind. Read the period next to the height on every day card above, and watch for the afternoon westerly reinforcement that often stiffens the ride home.
Because the bank is shallow water standing in deep ocean, swell energy focuses over it — conditions on the bank itself can be rougher than the open-water forecast either side of it. Build margin into the plan: the best Cortez days in the outlook are the ones where wind stays light through the full window, not just the morning.
Cortez Bank forecast FAQ
How is the sea at Cortez Bank today?
As of Sep 4, 2026, the SeaLegs AI verdict for Cortez Bank is NO-GO. Friday is a NO-GO despite light-to-moderate 9-17 knots NW to WNW winds (gusting up to 23 knots overnight) because of a confused cross-sea: a SW swell at 7-11 second periods is crossing a separate NW wind-wave pattern, creating two wave trains from different directions that produce awkward, unpredictable boat motion with no comfortable heading. Wave heights build steadily through the day from around 5 feet to over 6.5 feet by evening, and conditions deteriorate further overnight as waves are classified bad from 8:00 PM onward. Even though winds look manageable all day, the mixed sea state makes this an unsafe day for recreational vessels.
How far is Cortez Bank from San Diego?
Cortez Bank lies about 100 miles off San Diego — a genuine open-ocean crossing with no shelter along the way, which is why the multi-day outlook matters more here than for nearshore trips.
How often is this San Diego offshore forecast updated?
The forecast on this page is rebuilt every morning from the latest marine model data, and the SpotCast card refreshes live in your browser. The date stamp above the outlook shows when it was last generated.
What do GO, CAUTION, and NO-GO mean?
GO means conditions are favorable for most recreational offshore boats. CAUTION means marginal — pay close attention to swell period and the evening wind trend before committing to the crossing. NO-GO means conditions are hazardous for small craft and the trip is best postponed.
Can I get a forecast like this for my own spot?
Yes. In the free SeaLegs AI app you can drop a pin anywhere — the 9-Mile Bank, the Coronados, or your own waypoint — and get the same AI-rated marine forecast, plus fishing reports and trip planning.
What is the water temperature at Cortez Bank today?
As of Sep 4, 2026, the satellite-derived sea surface temperature at Cortez Bank is about 70.8°F, with chlorophyll around 0.15 mg/m³ (blue-green transition water). The SST and chlorophyll charts on this page are rebuilt every morning from the SeaLegs AI DeepCast satellite pipeline.
More offshore forecasts
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